first proposal to fix GSC bit exact decoding (81193b3f) · Commits · SA4 / Audio / IVAS BASOP

lib_com/gs_bitallocation_ivas_fx.c

+85 −10

Original line number	Diff line number	Diff line
		@@ -13,7 +13,9 @@
		#include "stl.h"

		static void reajust_bits_fx( Word32 *bits_per_bands, const Word16 st_band, const Word16 end_band, const Word16 sum_bit_in, const Word16 bit_bdgt_in );

		#ifdef FIX_802__NON_BE_DECODING
		static Word32 Find_bit_frac( const Word16 nb_band, const Word16 remaining_bits );
		#endif
		/==================================================================================/
		/* FUNCTION : void bands_and_bit_alloc_ivas_fx(); */
		/----------------------------------------------------------------------------------/
		@@ -460,8 +462,11 @@ void bands_and_bit_alloc_ivas_fx(

		set32_fx( bits_per_bands, 0, MBANDS_GN );
		/bit_fracf = (1.0f/nb_bands)(SWB_bit_budget); */
		#ifdef FIX_802__NON_BE_DECODING
		bit_fracf = Find_bit_frac( nb_bands, extract_l( SWB_bit_budget ) );
		#else
		bit_fracf = L_mult( div_s( 1, nb_bands ), shl( (Word16) SWB_bit_budget, 2 ) ); /* Q18 */

		#endif
		nb_tot_bands = sub( nb_bands_max, 6 );
		nb_tot_bands = s_min( nb_tot_bands, 16 );

		@@ -642,7 +647,11 @@ void bands_and_bit_alloc_ivas_fx(
		ELSE
		#endif
		{
		#ifdef FIX_802__NON_BE_DECODING
		bit_fracf = Find_bit_frac( st_band, bit_tmp );
		#else
		bit_fracf = L_mult( div_s( 1, st_band ), shl( bit_tmp, 2 ) ); /* Q18 */
		#endif
		}
		/*------------------------------------------------------------------------
		* Complete the bit allocation per frequency band
		@@ -968,43 +977,109 @@ static void reajust_bits_fx(
		Word16 bit_bdgt, sum_bit;

		incr = 1;
		IF( end_band < st_band )
		move16();
		if( LT_16( end_band, st_band) )
		{
		incr = -1;
		move16();
		}

		IF( bit_bdgt_in < sum_bit_in )
		IF( LT_16( bit_bdgt_in, sum_bit_in ) )
		{
		amount_to_add = -1;
		bit_bdgt = sum_bit_in;
		sum_bit = bit_bdgt_in;
		move16();
		move16();
		move16();
		}
		ELSE
		{
		bit_bdgt = bit_bdgt_in;
		sum_bit = sum_bit_in;
		amount_to_add = 1;
		move16();
		move16();
		move16();
		}

		i = st_band;
		WHILE( bit_bdgt > sum_bit )
		move16();
		WHILE( GT_16( bit_bdgt, sum_bit ) )
		{
		// if (amount_to_add > 0 \|\| (amount_to_add < 0 && bits_per_bands[i] > 1))
		IF( amount_to_add > 0 \|\| ( amount_to_add < 0 && bits_per_bands[i] > 262144 ) )
		/* if (amount_to_add > 0 \|\| (amount_to_add < 0 && bits_per_bands[i] > 1))*/
		test();
		test();
		IF( amount_to_add > 0 \|\| ( amount_to_add < 0 && GT_32( bits_per_bands[i], 262144 ) ) )
		{
		// bits_per_bands[i] += amount_to_add;
		/* bits_per_bands[i] += amount_to_add;*/
		bits_per_bands[i] = L_add( bits_per_bands[i], L_shl( amount_to_add, Q18 ) );
		move32();
		sum_bit = add( sum_bit, abs_s( amount_to_add ) );
		}

		i += incr;
		IF( i == end_band )
		i = add( i, incr );
		IF( EQ_16( i, end_band ) )
		{
		i = st_band;
		move16();
		}
		}

		return;
		}
		#ifdef FIX_802__NON_BE_DECODING

		/-------------------------------------------------------------------
		* Find_bit_frac()
		*
		* Computes the fraction of the remaining bit budget to allocate to the bands
		-------------------------------------------------------------------/

		static Word32 Find_bit_frac(
		const Word16 nb_band,
		const Word16 remaining_bits )
		{
		int16_t inv_bandQ15;
		int32_t L_out;

		inv_bandQ15 = 6553;
		move16();
		IF( nb_band == 7 )
		{
		inv_bandQ15 = 4681;
		move16();
		}
		ELSE IF( nb_band == 3 )
		{
		inv_bandQ15 = 10922;
		move16();
		}
		ELSE IF( nb_band == 4 )
		{
		inv_bandQ15 = 8192;
		move16();
		}
		ELSE IF( nb_band == 5 )
		{
		inv_bandQ15 = 6536;
		move16();
		}
		ELSE IF( nb_band == 10 )
		{
		inv_bandQ15 = 3277;
		move16();
		}
		ELSE
		{
		#ifdef DEBUGGING
		printf( "1/%d NOT DEFINED in Find_bit_frac\n", nb_band );
		#endif
		}
		L_out = L_mult( inv_bandQ15, shl( remaining_bits, 2 ) );

		return ( L_out );
		}
		#endif

		#endif

lib_com/options.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -148,6 +148,9 @@
		#define FIX_729_MISSING_RESCALING
		#define FIX_798_LSF_SECONDARY_CH_MISSING_CODE /* Adding the missing code to properly render the secondary channel of TD stereo*/
		#define FIX_798_WRONG_CPY_OF_PITCH /* The copy of the pitch from primary to secondary channel was wrong AND safety check was really wrong */

		#define FIX_802__NON_BE_DECODING /* Fix possible difference float and fixed point when computing the GSC bit allocation */

		/* ################## End DEVELOPMENT switches ######################### */

		/* clang-format on */